Underwater mining device



y 29, 1952 K. o. F. JACOBSEN 2,605,090

' UNDERWATER MINING DEVICE Filed Jan. 23", 1950 2 Sl-lEETSSl-1EET 1 7'0 FROM 5w: r/o/v PRESSURE PUMP PUMP IN VEN TOR. K. 0504/? E JACOBSEN wiwym July 29, 1952 K. o. F. JACOBSEN 2,605,090

UNDERWATER MINING DEVICE Filed Jan 25, 1950 2 SHEETS-SHEET 2 INVENTOR. K 0504/? l- /Acoasav M Ew W A Tro ENE Y5 Patented July 29, 1952 UNDERWATER DEVICE I 7 Karl Oscar F. Jacobsen, seam wash. f 1 Application January 23, 1950, Serial No. 140,054

11 Claims. 1

This invention relates to a device and method for mining of underwater placer gold and other heavy precious metals, and is herein illustratively described by reference to its preferred application, namely as a portable one-man operated means of taking gold and platinum, for instance, from creek bottoms or the shallows of other bodies of water, under which the alluvial material is largely of a more or less finely divided nature, including fine gravel, sand or silt.

Much of the worlds remaining gold resources is to be found in places such as those mentioned above where either because of inaccessibility or the nature'of the deposits, it is considered impracticable or uneconomical by previous means to undertake mining operations with mechanized equipment. Some of these deposits are rich enough that they are being worked at the present day by the laborious panning process. This technique; despite its limitations, offers the advantage over prior mechanized apparatus in that frequent moves may be made at little trouble and expense. Much of the gold in a deposit, especially that lying underwater or directly on bedrock cannot be recovered by panning, however. n

An important object of my present invention is to enable mining of such placers by an inexpensive mechanized system which greatly increases the volume of deposit which may be handled in a given time, reduces the physical labor involved and can readily be accomplished by apparatus sufliciently compact and light in weight to be packed to any workable area by one mule, for

example.

Anotherobject is'to make it more conveniently possible for the miner to reach and process underwater deposits, and especially to enable recovery of gold lying directly onbedrock whereas economically therefrom, there was extremedifii- .In attaining the foregoing andother objects,

1 the .present inventionutilizes the principle of .hydraulic suction by which silt, sand and fine gravel containing nuggetsand flakes of gold are ,drawn from the bottom through apparatus which gets. .ment of the flow at the suction inlets so that 2 separates the heavier nuggets from the flakes and other materials and delivers the latter to a suitable disposal point for working and recovery of the gold flakes according to a selectedprocess such as sluicing. In order to draw the loose materials into the suction inlet of the apparatus at a more or less steady rate, the heavier gold particles along with the lighter materials, thebottom in the vicinity of the suction inlet is agitated by jet streams of water directed in fixed relation to the inlets. g

Preferably the apparatus comprises a plurality of suction inlets directed downward and inward at an incline in relation to, and toward, a common axis, and a pluralityof agitator jet directed alongside the inlets and somewhat tangentially to create a swirling cloud of water and bottom materials from which the material is drawn into the apparatus more efiectively than if there were no agitation provided. The streams from the suction branches merge above a trapvinto which drop most of the. heavier gold particles or nug- Provision is made for convenient adjustwhen an area of abedrock bottom has been swept of most of its light weight loose materialthe amount of suction may-be. increased in orderrto recover. gold particles lying ..ldirectly on the bed:- rock and more difiicultto raise. 1:

These and other features, objects and advantages of the invention includingcertain details of construction of its preferred and herein illustrated form willnow be described moretfully by reference to theaccompanyin'g: drawings. .1 Figure 1 is anisometric view of the portabl nozzle unit which the operatorcarries and applies to the'stream bed to pick up the loosematerials. Figure 2. is a bottom view. of. the. nozzle .unit. Figure 3. is a vertical sectional view of the lower or nozzle end portion or the nozzle. unit shown in operation, theview being takenonv a plane containing the axis of the lower endportion of the main suction pipe in the unit,

The drawings do notshow all of the apparatus s in c n ionitht e; o z e -.-unit, i...-.e.,

. the suction pump and the pressure. pump coupled by hose to the suction and jet nozzle pipes, respectively, of the nozzleunit, and the auxiliary a paratus into which the suctionpumpsidischarge is delivered for separation of gold particles from the other materials, these being components which can be of conventional'for'rnif desired. 1 i V In Figure .1, thebroken-oli section of hose-l0 fastened to the short length of pipe I! at the upper end of the nozzle unit, will extend'to the intake side of a suction pump, while the brokenofi section of hose l4 fastened to the length of pipe 16, also at the upper end of the nozzle unit, will extend to the delivery side of the pressure pump. These hoses are of a suflicient length to permit the nozzle unit, held by handle IE, to be carried about by the operator for coverage of a sizable stream bed area around the temporary pump installation. The pumps may be driven by a small gasoline engine or other power unit which, together with the other apparatus, does not impair the portability of the complete set of equipment. In a typical case, the nozzleunitwill weigh in the vicinity of pounds whereas the pump units and gasoline engine may be selected to weigh less than pounds for portable operatlons.

Standing in or over shallow water the operator applies the lower or nozzle and of the unit to the stream bedZD as shown in Figure 3 While holding the elongated unitgenerallyupright by its handle l-8.' In most instances the overall length of the unit between its nozzle end 22 and its handle l8 should be about '3 feet for maximum comfort and convenience-to the operator. When the nozzle'unit is' used to a depth in excess of about two feet, however, it is preferred to replace thelhandle extension 2 4 with a longer one, the operators workmg kit preferably including extensions of various lengths for this purpose. I I

-The nozzle unit has a main suction pipe 26 which extends from its somewhat largersuction outlet pipe 12 downward along a sinuousorother predominantly inclined path to a generally straight. lower end portion 28 which is disposed substantially verticalin the vertical operative position of the unit, and is located generally at theunits vertical axis.- Suction branch pipes 36 extend radially outward from the union fitting 32 threadedonto the lower end-of the main suction pipe 26. Preferably these branch-pipes intersect thelmainrpipes lower end portion 28 or imibn 32'genera'lly at right angleslas shown in Figure 3, althoughis ome incline. would not be objectionable. v Preferably the nozzle unit incorporates a plurality of these branch pipes 38 araianged 'symmetrically in ,equiangular relationship .about the axis of union 32 as shown .inFigure 2,

there being fourisuch lbranchspipeslin the illus- -trated case." :Theselbranch pipes are of consid- -erably-.zsmallerl. internal size than the main suction' pipe 526; which in turn is somewhat smaller than the .'interna;l..size of the/suction outlet pipe Land the connected suction hose H1 leading to 'theqpump; Inrtermsof standard pipe sizes the pipe lzlmay' be a l' e inch pipe, the pipe-25 'a linchpipe and thefbranch suction pipes-38', inch pipes in a practical case. By employing "branch suction pipes ofthat order of magnitude, -the larger gold nuggets are more readily lifted in --theni by the suction stream because there is no greatamount of room for'theupwardly moving r-the reason that the gem parunes an best -be drawn up by fsuction through a pipe'if the pipe -iszinclined andits lower wall thereby affords-some support to the particles',' the main suction pipe 26 .islgiven a predominantly inclined orsinuous form in which there are no long, directly vertical paths pipe section .28 where the branch streams merge,

=to;-.be:.traveled by the upwardly moving particles I etherein. The short vertical bends 26" are not objectionable in this regard because the inertia of the particles is sufficient to enable them to be carried up these short vertical ascents between successive inclined sections of the pipe. Because of similar considerations, the suction branches 30 extend horizontally outward from the union 32 and then are turned downward and inward at an incline generally toward the central vertical axis of the nozzle unit. Gold nuggets traversing the horizontal sections of the branches entering the interior of the main suction pipes lower portion attain their greatest velocity, hence are not likely to drop back out of the suction branch pipes once they reach the horizontal sections. The lower ends of these suction branches are spaced apart by an appreciable distance but preferably are directed toward a common point of intersection appreciably below the unit as shown. Loose particles drawn into these suction branches through their open lower ends travel upwardly along inclined paths and, then horizontally-into the interior of the union 32 which effectively con,- stitutes a shortextension of the vertical lower end portio 25. f the main s t o p p sho n in'Eigure Bthe suction streams from the branch pip s '30, me to, f mer. up l flow n co m f Water and W er-borne ma rials. n the mainsll np pe 2 T e nozzle it has. a nuee t raonsi tin preferably of a short length of pipe 3i" threaded into the lower end of the union fitting 32 to form a downw at onr f e Qwerend-p rti n. 2 .1 of the m i ct on ipe,- This t p p itwminat at a o at on s me h above th lower ends of the branch pipesg ml and carries a short union 36 into which a removable; plug 38 is threaded to close off its lowerend. Some the gold particles which enter the interior of the vertical suction pipe section 28 continue to be carried with the upwardly'moving suction stream w e? Q a on u en wh f nders. t m comparatively light for their amount of surface area, Gold flakes are ofsuch a configuration and will'bedrawn out, through the main suction pipe 28 and the suctionhose Hlxvith the lighter materials picked up by the nozzle unit. However, gold nuggets are generally. 3 somewhat round, hence comparatively heavy for their amount of surface area so as to be carried upward less easily than the, flakes by the suction stream. 'ljherefore, upon entering the interior of the-vertical these nuggets will drop into thebottom of the trap pipe 34 and accumulate; 1

I This separation process resulting in accumulationof. gold nuggets in the. trap below the intersection of the suction bra'nches 30 is aided; by

turbulence of the merging branch stieamsand bythe. fact that the lower end portion 28 of the main suction pipe 26 is substantially vertical. and afiords no inclined or horizontal surface. upon which the, gold particlesmay rest in aid of being swept upward by a the moving suction stream. LHowever, the length of the verticalksectionuia should not be excessive, since eventhe gold .fl'ake's normally require some amount of support to insure they will be carried upward with the .sucti'qni tre rn- Qf a e ocity a tainabl by, a pump Qf he i izeq pl t d for ort e sa e; 'In order to avoid the possibility of ,larger pieces of gravel becoming lodged inthe' suction branch pipes ,30 and blocking flowtherein; the lower'ends of these branches are ifitted, with caps 1 40 aperturedto a size of opening somewhat smaller than the interior cross section of the suction branches so that only those pebbles which will 'pass' freely through'the suction branches are admitted into them. The size of these apertures is large enough, however, to pass any gold nuggets which will be found in the great majority of placer deposits. 7

. As a further feature of the suction piping of the nozzle unit, there is provided the by-pass suctionpipe 42 of V2 inch size in the illustrative case, having a flow control valve 44 and entering the union fitting 48 interconnecting the suction outlet pipe l2 and thesmaller main suction, pipe 26. The lower end of this by-pass pipe, provided with a cap having a restriction apertureto block entrance of too large pebbles, is open and is located inthe vicinity of the suction inlets 30 although appreciably abovethe same so that it .will draw alarger preponderance of water than do the suction inlets. 'When the nozzleunit is first being appliedto a bottom deposit of finely divided loose materials, the valve .44'will normallybe open and the flow through the main suction pipe. 26, hence through the suction branches 30, will be reduced by an amount corresponding tothe flow through the by-pass ipe 42. However, when a greater amount of suction is needed, as when the bulk of the loose materials is removed from the bedrock 48-(Figure. 3), except for gold particles which lie directly on the bedrock which in many years past has functioned as the riflied bottom of a sluice box to collect the gold, greater suction is obtained at the inlets 40 by closing the valve 44 so that all of the flow through the suction hose I0 must pass through the suction branches 30 and the main suction pipe 26. This it does at higher velocity and therefore with greater eifectiveness, as later explained, to draw the heavier gold particles into the suction inlets. Another reasonfo r reducing the-suction when first applying the unit to a deposit of loose materials is that the suction pump will operate more satisfactorily if the ercentage of solid material being drawn is not excessive. L

. Suction alone as a means of pickingup loose gold particles and other materials intermingled therewith fromthe bottom of a' body of water is in itself an idea which has been tried in various forms heretofore. Certain improvement features of the present invention relate to the provision of a portable nozzle unit having'a plurality of comparatively small suction inlet branches, the

discharge streams of which merge in a larger 'main suction pipe, both the branches and the ,main suction pipe preferably having inclined or horizontal surfaces to support the moving gold particles, the by-pass, the trap below the junc-- ture of the branches and the main suction pipe, and the other features ,of the suction components 'of the nozzle unit, illustrated and described,

separately and in combination.

A very important additional feature of the invention renders the nozzle unit far more efiective in picking up gold particles and surrounding materials, however, than could possibly be obto settle still lower by this-process Consequently gold: particles are not all recovered by such a 1 technique as eifectively as' desired. Moreover, if Such a suction orifice is directed perpendicularly 6 i to the surface of the deposit something. of the same result is obtained but with possibly somewhat lesser effectiveness. According to the. invention the bottom deposit is first or continuously agitated by jet streams discharging in the vicinity of the suction inlets toset the loose particles into motion, suspended in water, so that the gold particlesas well asthe other ma terials can be drawn readily intothe suction inlets. The jets raise the goldparticles off their bed and the resulting motion of the water tends to suspend them long enough to be drawninto the suction inlets. I y

In the preferred and illustrated case, the nozzle unit has a plurality of agitator or force jets 48 corresponding in number to the suction inlets 40. Each such jet orifice directs its stream at an incline downward, somewhat inward, and in a tangential direction along the outer and lower edge of a corresponding suction inlet 40 (Figure 2),. Sincethese jets are directed generally downward the effect is to stir the bottom vigorously and raise the loose materials. Because of the tangential directionalcomponent of the jets, their combined eifect is to create a swirling cloud of water and raised bottom materials in the vicinity of the suction inlets. Borne by the swirling water, the loose materials are readily drawn into the suction inlets 40.

The action is illustrated diagrammatically in Figure 3, showing the manner in which'the nozzle unit eats its way through the loose materials to bedrock. A bottom area will usually be worked in this wayuntil the bedrock is largely swept clean of most of its loose deposit. Thereafter the same area will be swept again for loose gold particles lying directly upon the bedrock, with the nozzle unit operating at higher suction by closing off the valve 44 in the by-pa'ss pipe 42. It is considered that a greater amount 'of' suction is needed for this final sweeping or cleanup operation of a bedrock area than is needed during the initial stages, because the jet streams are more effective to raise and swirl gold particles embedded in other and lighter loose materials than they are when the gold particles are lying directly on a solid bottom; in the latter case a greater amount of suction is desirable for drawing the particles into the suction jinlets.

The agitator jets 48 are formed by the lower ends of the pressure "delivery branch pipes 50, preferably pinched somewhat as shown to create afan-shaped jet stream. These pipes branch from the lower end of the main pressure pipe 52 connected to the inlet pipe [6. A union 54 is bored to receive the upper ends of the branch pipes 50 and fits over the lower end of the main pressure pipe 2. plugged and is tackwelded to the suction pipe 26 at 56 as shown to rigidify the piping structure as a whole.

A circular shield and nozzle support 58 surrounds the loweror nozzle end 22 of the unit and serves as a mounting by which the suction pipe branches 30 'and the pressure pipe'branches 50 are supported in their desired relationship and shielded, so that despite considerable abuse they will not be bent or twisted outlof shape.

The best manner of using the-novel apparatus will depend to a degree upon' the nature of I claim as my invention: 1

1-. In underwater placer mining apparatus a nozzle unit comprising a generally axially ex- The lower end of the union is 7 tending suctioni-conduit having-a lowerend-portion disposedgenerally upright in the nozzle unit s operative position, a plurality of suction branch conduits (if-substantiallysmallersize branching outward fromsaid lower end portion and turned downward and generally inward at an incline to the vertical,- said branch conduits terminating in lower end=portionsorming silotion inlets for drawing or loose bottom materials into said branchconduits pressure conduit means including a-plurality of-downwardly extending pressure branch'conduitsterminating in lower end portions forming similarly-directed force jets directed generally downwardly and appreciably inwardly and tangentially about the nozzle units-axis'to createa'vortex' swirl of loose bottom materialsin-the vicinity of said suction inlets to be drawn into said suction inlets:

2. In underwater placer mining apparatus, the nozzle unitdefinediincla'imi further comprising a by-pass conduit connected at its-upper'end to the suction conduit above the latters lower end portion and "extending downwardly therefrom the vicinity of but appreciably above the suction inlets, to draw water through said bypass conduit and thereby reduce'the suction now through the suction conduit, and adjustable flow control valve means to varyrthe suction fiow in said by-pass conduit relative to that in said suction conduit.

3; The underwater placer mining nozzle unit comprising a suction conduit having a lower end portion disposed generally upright in the units operative position, said suction conduit tion beneath said suction conduit lower end portion to receive nuggets dropped from 'thesuction stream where the branch streams merge.

4. The unit defined in claim 3, and suction inletiorifice means having 'an inlet opening therein slightly smaller than the interiorcross section of the suction branch conduits for excluding larger pebbles which might lodge therein and block flow. V

5; The underwater placer mining nozzle unit defined in claim 3, additionally comprising a plurality of downwardly directed pressure jets located in the vicinity of said suction inlets and directed generally downwardly, appreciably inwardly and in corresponding generally tangential directions to create a vortex swirl of water-borne bottom materials around said suction inlet'for influx thereof into said suction inlets.

'6. The underwater placer mining nozzle unit defined in claim 3, additionally. comprising a plurality .of downwardly directed pressure jets located in the vicinity of-said suctioninlets and operable to create a swirl of water-borne-bottom materials iaround said-suction inlets for influx thereof-into said suction inlets.

'7."Ihe underwater placer mining nozzle unit comprising a imainr suction conduit having a 7 lower end portion disposed generally upright in the units operative position and having an upper end portion adapted for connection to a source of suction, a plurality of suction branch conduits of substantially smaller size than said main suetion conduit and radiating outwardly from "the vicinity of said lower end portion thereofand then turned downwardly and inwardly at :an

incline to the general axis of such lower end portion to form suction inlets grouped generally uniformly about such axis, and suction inlet orifice-means on thelends of the respective suction inlets restricting the inlet openings thereof to a size slightly smaller than the interior cross section of said suction branch conduits for excluding larger pebbles which might lodge prising a nozzle unit disposed generallyupright in the operative position thereof and having a plurality of pressure jets, means supportingsaid pressure jets grouped about the general upright axis of the nozzle unit and directed'generally downward and appreciably tangentially in the same sense about such axis to create a vortex swirl of loose bottom" materials when positioned operatively at the bottom of a body of water, and suction conduit "means-having at leastone suction inlet within such vortex swirl createdby said pressure jets and drawing water-bornebottom materials thereinto for conveyance to a separating point.

l0. Underwater, placer mining apparatus comprising a suction conduit, a pressure" conduit extending generally alongside said suctionconduit, both being disposed generally upright in the operative position'of such apparatus, a plurality of suction branch conduits radiating generally outwardly "from said suction conduit and then curving generally downwardly and inwardly at an acute anglerelative thereto to form suction inlets grouped about the axis of said suction conduit, and a pluralityof pressure branch conduitsradiatin'g generally outwardly 'from'said pressure conduit and then curving downwardly in the spaces between said suction branch conduits to form pressure jets in the vicinity of said suction inlets, said pressure jets being 'directed generally tangentially invasimilar sense about said axis and appreciably inward relative to the. general axis of said pressure conduit to create a vortex swirlof loose bottom materials to be drawn oil by suction through said suction inlets. v I i ll. Underwater placer mining apparatus comprising a suction conduit, a pressure conduit extending "generally alongside said suction conduit, both being disposed generally upright in the operative position of such apparatus, a plu- 'rality of suction branch conduits radiating genpressure conduits-andthen curving downwardly in the spaces between said suction branch conduits to form pressure jets in the vicinity of said suction inlets; said ,pressure jets being di- 9 10 rected generally tangentially in a similar sense about said axis and appreciably inward relative REFERENCES CITED to the general axis said Pressure wnduit to The following references are of record in the create a vortex swirl of loose bottom materials file of i p t to be drawn oil by suction through such suction 5 inlets, and a ring-like tubular member generally UNITED STATES PATENTS surrounding said suction inlets and pressure jets Number Name Date slightly above the lower ends thereof. 532,183 Pike Jan. 8, 1895 2,284,459 Watkins May 26, 1942 k; OSCAR F. JACOBSEN. 10 

